2021 Used The Acaia Lunar scale is the most famous professional scale for espresso extraction. [1] Key Specifications Accuracy: Weighs accurately up to 0.1 grams with a maximum capacity of 2000 grams. Design: A small, waterproof body specifically designed to fit espresso machine drip trays. Features: Flow-rate indicator, ultra-fast response, and a rechargeable battery via port that lasts 30-40 hours. Connectivity: Supports Bluetooth for connection to the Acaia app.: